11/06/2025
This was a LONG but great project!
The customer called and asked if I could help him since no one knows what's going on in here. Upon arrival, I was shocked to see a second, I repeat, a second air-to-water heat pump in the USA 😀I came across.
In Europe, systems like this are very popular and efficient; almost all houses have radiant heat, which means PEX tubing is installed under or inside the floor. This system is great because you do not need to heat water to 160-180°F, as in traditional boilers; instead, you need around 105°F water to flow through the piping. Since there is insulation radiating heat upward, even at a 68°F set point in the room, you feel significantly warmer, as you are essentially walking on a heating surface. Low temperatures like these allow you to lower the costs of heating your house and improve comfort.
For cooling, this house utilizes The Unico System high-velocity system, where cold water is pumped to the units, and fans push cold air through small openings to the entire house.
Two outdoor Chilltrix 50 heat pump units, manufactured by The Unico System, produce either cold or hot water, which is pumped into a buffer tank and distributed to the Fan Coil Units for cooling or the Radiant Floor system for heating. Units will automatically switch based on the outdoor temperature to provide the correct water temperature.
Additionally, one of these units is responsible for heating another tank, which is used for domestic hot water. It is 80 gallons, so there is plenty of water available for customers, and the unit has sufficient time to adjust to the desired temperature, ensuring it remains consistently hot at 120°F.
The customer was hesitant about whether to install new heat pumps or remove everything and install something else, as the previous plumber who came to inspect and fix the issue had done little and left the units filled with water over the winter, resulting in heat exchangers bursting due to freezing. I assured him that this is the best system for his big house, and once everything is done, he will be pleased! I informed him that I will use a glycol mixture to prevent freezing, so he doesn't have to worry about it ever.
This morning, he called asking how he can lower the temperature, as it feels like a sauna at 76°F. 🤣 Yesterday, I warned him not to set it to 76°F because these are new-generation pumps; they are great units and are going to deliver what he is asking for. So, be careful about setting the thermostat, as it will get very hot!
My only advice was "crack a window and wait" for it to cool and set your thermostat at a lower temperature, I suggest 68F, and see how it feels. If it is slightly cold, put it to 70°F. Well, a few hours later, he said at last it cooled off, and now it is 68F, it feels fantastic, and he will leave it at that temp 😀
